Building pool walls with identical modular panels assembled together is known.
The documents EP0382649 and FR2765909 disclose generally rectangular modular panels made of plastic material, the width of which (of the order of a few tens of cm) is reduced relative to the height (of the order of 120 cm). The panels comprise a main body having an inner surface that constitutes the inner wall of the pool and an outer surface provided with a vertical, hollow reinforcing element, adapted to receive concrete and to form a vertical column for holding the structure (also called a chimney).
The main body of each modular panel is obtained from plastic injection molds having a planar surface widthwise and lengthwise, to form the inner surface of the main body; the inner surface is expected to be planar after assembling and formwork, to provide a correct planarity of the whole inner wall of the pool.
A defective planarity has, however, been noted in the inner faces of the pool walls built with modular panels of the state of the art, after mounting and formwork thereof. A defective planarity more particularly results in a ripple effect of the inner wall of the pool, which is undesirable for the end user.